function bigimg(){
  var bbox = document.getElementById("box");
  var bmove = document.getElementById("move");
  var bbimg = document.getElementById("bimg");
  var b_bimg = document.getElementById("b_bimg");
  
  
  bbox.onmouseover = function(){//鼠标移动到box上显示大图片和选框
    bbimg.style.display="block";
    bmove.style.display="block";
  }
  bbox.onmouseout = function(){//鼠标移开box不显示大图片和选框
    bbimg.style.display="none";
    bmove.style.display="none";
  }
  
  
  
  bbox.onmousemove = function(e){//获取鼠标位置
    var ev=e||window.event;
	var Stop=document.documentElement.scrollTop||document.body.scrollTop;
	var Sleft=document.documentElement.scrollLeft||document.body.scrollLeft;
	
		  var x = ev.clientX+Sleft;//鼠标相对于视口的位置
    	  var y = ev.clientY+Stop;
	
	  //var x = ev.clientX+document.body.scrollLeft-document.body.clientLeft;//鼠标相对于视口的位置
    //var y = ev.clientY+document.body.scrollTop-document.body.clientLeft;
	  
    var t = bbox.offsetTop;//box相对于视口的位置
    var l = bbox.offsetLeft;
	
	//计算move的位置
    var _left = x - l - bmove.offsetWidth/2;
    var _top = y - t -bmove.offsetHeight/2-110;
	
	//限制选框范围
    if(_top<=0)//滑到box的最顶部
     { _top = 0;}
    else if(_top>=bbox.offsetHeight-bmove.offsetHeight)//滑到box的最底部
      {_top = bbox.offsetHeight-bmove.offsetHeight ;}
    if(_left<=0)//滑到box的最左边
     { _left=0;}
    else if(_left>=bbox.offsetWidth-bmove.offsetWidth)//滑到box的最右边
      {_left=bbox.offsetWidth-bmove.offsetWidth ;}
    bmove.style.top = _top +"px";//设置选框的位置
    bmove.style.left = _left + "px";
	
	//计算移动的比例
    var w = _left/(bbox.offsetWidth-bmove.offsetWidth); 
    var h = _top/(bbox.offsetHeight-bmove.offsetHeight);
	
    var b_bimg_top = (b_bimg.offsetHeight-bbimg.offsetHeight)*h;//计算大图的位置
    var b_bimg_left = (b_bimg.offsetWidth-bbimg.offsetWidth)*w;
    b_bimg.style.top = -b_bimg_top + "px";//设置大图的位置信息
    b_bimg.style.left = -b_bimg_left + "px";
  }
    
}// JavaScript Document
function A(i){
	window.localStorage.setItem(i.toString(),0);
	//购物车里面商品的数量
	  var numb=document.getElementById("numb");
	  var l=window.localStorage.length;
	  numb.innerHTML = l;
}